Hydraulic snubber



, June 14, 1927.

A. L. POUDRIER HYDRAULIC SNUBBER Filed July 26, 1926 2 Sheets-Sheet l Mum-1 W; I 0 21 2 0 udrz'er' v Filed July 26, 1926 2 Sheets-Sheet 2 g aww lbdz B) UQLJoadrzer.

abtom1ma/ Patented June 14, 1927.

UNITED STATES PATENT OFFICE.

MND L. POUDRIER, 0,! LOS ANGELES, CALIFORNIA.-

HYDBAULI C SNUBBEB.

Application w m 2c, 1926. Serial Io. 125,030.

This invention relates to hydraulic snubbers for use on automobiles and other like vehicles.

More especially the invention relates to when the casing is assembled the rock shaft will be securely held therein.

A third important object of the invention is'to eliminate the necessity of an'exhaust passage at one side of the piston and to eliminate the corresponding necessity of pro-.

viding guide means to hold the piston in a particular position.

A fourth important object of the inven-- tion is to improve the construction of the ball valve and piston arrangement by the substitution of a hollow iston with a perforated cu to hold theball valve in position.

Afifth important object of the invention is, to improve the action of the device by such an arrangement of the oil passage in the piston that the rebound is at first quite free but is gradually checked so that at no time do the passengers in the vehicle experience rough shocks.

A- sixth important object of the invention is to provide an improved form of such check wherein there will be resistance not only to the rebound but also in the opposite direction. 7

With the above and other objects in view as will be hereinafter ap arent the invention consists in general 0 certain novel details of construction and combinations of parts hereinafter fully described, illustrated in the accompanying drawings and specifically claimed. I

In the accompanying drawings like characters of reference ind1cate like parts in the several views, and:

Figure 1 is a vertical median section .ble acting.

through a shock absorber constructed in accordance with these improvements.

Fi re 1.

Figure 2 is a section on the line of igure 3 is a section on the line 3 --3 of I Figure 1.

Figure 4'is a detail perspective view of a ball valve cage.

Figure 5 isa viewsimilar to Fi re 1 but showing a modification, the same ing dou- Figure 6 is an enlarged detail horizontal section showing regulating valve as used herewith.- v

In the form oftheinvention shown in Figures 1 to 3 inclusive there is provided a casing having a lower portion 10 and an upper. portion I 11. In the bottom of the lower portion there isfformed a cylinder 12 having a closed lower-end 13, this cylinder being enlarged at its upper end as shown at 14. Vertically slidable in the cylinder 12 is.

a hollow piston having annular walls 15 and a top16 provided centrally with a port 17. Furthermore this piston has on its exterior a longitudinal slot 18 which gradually dee ens from the upper end of the piston to t e lower, the slot preferably being of the same width throughout its length. Normall closing 'the port 17 is a ball valve 19 whic is forced uprward to closejsaid port by a spring 20. he lower end of this spring is supportednon the bottom of a valve cage 21 hav ng suitable perforations or openin s for the passage of fluid andbeing provided with a flange 22 at its open upper end. This flange 22 is of slightly less diameter than the diameter of the bore of the piston. The cage is held up in the piston and the piston ur ed to its raised position b means of a 001 ed spring 23, the upper en whereof surrounds the cagp 21 and bears a ainst the under side of t e flange 22. The ower end of this spring rests on the bottom 13. In the top and bottom sections of the casing are formed half bearings 24 wherein are received the ends of a rock shaft 25 which project slightly outwardly in front of the casin and carries a spring lever 26 having a roun ed end 27 provided with-a bolt opening 28 so that a strap 29 may be connected to the lever by a bolt 30. This strap is connected to the under frame of the vehicle, the axle, or other part which moves relatively to the vehicle body as the springs are compressed and expanded. Formed on the shaft 25 is a curved rock arm 31 the end of which bears on the to 16 of the piston. The casing is provided with apertured lugs 32 by which may be bolted to the body frame of the vehicle and the two sections of the casin are suitably held together by bolts 33. X filling opening provided with suitable clo sure 34 is formed in the upper section 11 of the casing. Packing 35 serves to prevent leakage of oil around the shaft 25.

The device as here shown is in the position which it will take under the influence of the under body of the vehicle moving vertically toward the .upper body or' body proper and thus compressing the vehicle springs. On the rebound, these springs seek to expand and pull the lever 26 downwardly. Through the cam 31 this tends to force the piston 15 downwardly. With the casing filled with oil, as is intended, the oil will flow through the passage 18. At first this flow will be quite free owing to the relatively great depth of the lower end of the slot but the escape of oil from beneath the piston is gradually checked by the decrease in efi'ective cross-sectional area of this slot towards its upper end. Consequently the checkin or snubbing is gradually increased untilel parts gently come to rest with the springs in their normally expanded condition. If the car, in this normal condition, strikes an obstruction or bump the springs will again be compressed. Upon this taking place the strap 29 will be slackened so that the lever 26 is free to move upwardly and this upward movement is accomplished by the action of the spring 23 forcing the upward end, through the rock arm 81, moving said lever upwardly. Of course, during this upward movement of the piston the ball valve 19 will open so that there will be free passage for the oil. The instant the motion of the lever 28 is checked by the strap 29 becoming taut the ball valve 19 will close and the parts will be ready for the rebound.

In the form of the invention shown in Figure ti the casing is divided, as before, into lower and upper parts 35 and 36 but the lower part in this instance is provided with two cylinders 37 and 38. The cylinder 37 holds a piston 39 identical in construction with the piston 15. The c linder 37 controls the rebound just as in t e previously described form. In the cylinder 38 is a piston of the same general form as the piston 39 but this piston 40 is provided with an escape groove 41 which is of uniform depth for a short portion of its upper end as at 42 and then tapers in depth as does the groove in the other piston. Both of these plstons are provided with the usual ball valve 43 held by a lever on sai a spring 44 carried in the cage 45 and the cage is supported and the piston urged to raised position by the spring 46 as in the first form. In this form the rock shaft 47 is provided with two arms 48 and 49, the arm 48 engaging the piston 39 while the arm 49 engages the piston 40. This rock shaft also carries a lever 50 and screwed on the outer end of this lever is a socket member 51 for a sliding follower 52 held in position by a corresponding nut 53. This socket and follower 52 engage a ball 54 formed on the upper end of an arm 55 which is connected to the axle or some other art of the under frame. Through a suite le threaded opening in the wall of the cylinder 38 extends a threaded valve pin 56 which enters the groove 41 and thus adjusts the available area of such groove.

The parts are shown in position similar to Figure 1, that is to say, ready for the rebound. As before, downward movement due to the rebound is resisted by the cylinder 39 but as this downward movement takes place the piston 40 rises until the vehicle springs are normally expanded. In this form under the influence of shock compressing such springs the lever 50 tends to rise and at first this is freely accomplished since the oil can pass freely from beneath the piston 40 to position above such piston. As the piston 40 moves downwardly the decreasing effective area of the slot 41 gradually checks the downward movement so that the vehicle springs are brought gradually to rest in their compressive movement. Thus with the double acting form shown in Figure 5 the springs come gradually to rest both on the bound and the rebound.

There has thus been provided a simple and efilcient device of the kind described and for the purpose specified.

It is obvious that minor changes ma be made in the form and construction 0 the invention without departing from the material spirit thereof. It is not, therefore, desired to confine the invention to the exact form herein shown and described, but it is desired to include all such as properly come within the scope claimed.

Havin thus described the invention, what is c aimed as new, is:

1. In a hydraulic snubber, a casing adapted for connection to a vehicle part and havin a cylindrical bore in its lower art provi ed with an enlarged up er en a piston fitting the lower part 0 said bore and havin a passage extending therethrough, a downwardly opening check valve carried by the piston and controlling said 0 ening, a spring urging the piston in one 1rection in the casing, a shaft extending transversely of the casing, a rock arm on said shaft on a 'ng the to of the piston, sfiinft adap for connection to a second part of the vehicle movable toed for connection to a vehicle part and having a cylindrical bore in its lower art provided with an enlarged upper and a. piston fitting said lower art of the bore, said piston having a cylin rical recess openinggdownwardly, the upper end of the piston having an axial port therein, said piston having a slot extending longitudinally of its exterior and deepened toward the bottom of the piston, a ball valve cage in the recess of the piston and provided with a flange at its upper end resting against the upper end of the recess, a ball valve in said cage normally closing the port, a spring in the cage to hold said valve closed, a second spring having its upper end surrounding the cage and bearing against the flange,' the lower endof the second'spring resting/on the bottom of the casing bore a shaft extending transversely of the upper part of the casin and projectin therefrom, a rock arm carried by the she the shaft adapted for connection to asecond part of thevehicle movable toward and from part.

3. In a hydraulic snubber, a casing adapted for connection to a vehicle 'part and having a cylindrical bore in its lower part provided with an enlarged u per end, a piston fitting the lower a part 0 said bore and having a passage extending therethrough, a downwardly opening check valve'cal'ried by the piston and controlling said opening, a spring urging the piston in one directionin the casing, a shaft extending transversely of the casing, a rock arm on said shaft enga ing the top of the piston, a lever on said .5 aft adapted for connection to a second part of the vehicle movable toward and from the first part, said piston having a slot extending longitudii'ially of the outside of the iston and increasing in depth towards the ttom of the pistonasaid casing having a-second similar bore in its lower part, the shaft being positioned between the axes of the two bores, a second similarspring pressed piston slidable in the second bore and provided with a similar check valve controlled opening and slot and a second rock arm on the shaft engaging the top of the second piston. a

' In testimony whereofl afiix my signature. and engaging thetop of the piston,1 and an' 4 operating lever on the 'projectmg'portlon of TARMAND POUDRIER. I 

